Discuss with students why dogs are often used as characters on television and in movies. Students should understand that dogs, as well as being appealing animals, are easy to train, and therefore make good "actors."

2.

Continue the discussion by asking students to name some dog "stars" of TV and screen. They might cite Lassie (a collie), Rin Tin Tin (a German shepherd), Beethoven (a Saint Bernard), Eddie (a Jack Russel terrier) from Frasier , Toto (a Cairn terrier) from The Wizard of Oz; or the dogs from 101 Dalmatians . )

3.

List the canine characters on the chalkboard, and determine with students the breed of each dog. (While many of the world's finest dogs, both on-screen and off, are of mixed ancestry, this activity focuses on the characteristics of particular breeds; therefore only dogs of known breed will be useful.)

4.

Ask students to express opinions based on prior knowledge or on direct experience concerning how realistically each breed is portrayed by the character listed.

5.

Assign each student or small group of students a dog breed from the class list, and have students research that breed to discover the qualities and traits for which it is known.

6.

Instruct students to create compare-and-contrast charts or Venn diagrams that show how closely the canine characters they chose resemble real-life members of their breeds. Do the on-screen dogs accurately represent their breeds? Do they have appropriate personalities? Do their roles on screen reflect their real-world traits? Are their physical appearances representative?

7.

Students can now use their research to write short reviews in which they either criticize or praise the films or TV shows for their portrayal of dog characters.

Adaptations for Older Students:
Have students replace dogs on screen with dogs in literature. Have them choose dogs from books of short stories they have read. You might suggest the following: Buck, the Saint Bernard/Scottish Shepherd in Call of the Wild by Jack London; Nana, the old English sheepdog in Peter Pan , by James Barrie; or Old Dan and Little Ann, the hunting hounds in Where the Red Fern Grows, by Wilson Rawls.

It's a sad fact that many dogs are taken to animal shelters when they grow older because their owners no longer want them or are unable to care for them properly. Speculate about steps that could be taken to alleviate this problem. Should we work to change owners' minds? Use tax money to build long-term dog shelters? Make it a crime to breed dogs without some kind of permit?

2.

When many people decide they want a pet dog, they simply head to the animal shelter or pet store and pick out the cutest one. There are many other factors to consider when choosing a pet, however. How big is your living space? What temperament would you like your dog to have? What physical characteristics do you find appealing in a dog? How much time will you be able to spend with your dog on a daily basis? Explain the things you would consider when selecting a dog for yourself.

3.

Describe how the world would be different if humans possessed as acute a sense of smell as that of dogs. What things about our daily lives would be different? How would we have evolved differently? What common human actions would change?

4.

Throughout history, dogs have been used in many working situations. Alaskan malamutes, for instance, have pulled sleds. Golden retrievers have chased down hunted ducks, and Saint Bernards have rescued trapped skiers. As society continues to advance, dogs are being used in many more working situations. Brainstorm a list of possible new ways in which humans might benefit from utilizing dogs in the future.

5.

Dogs and humans often have an interdependent relationship. Humans give dogs food and shelter, and dogs give humans companionship and work. How does this relationship compare to those between humans and fish, horses, cats, pigs, sheep, birds, and other domestic and farm animals? How about wild animals—everything from squirrels to zebras? Are these relationships similar at all? Why or why not?

6.

Some dogs perform rather dangerous jobs, like sniffing for bombs, chasing criminals, and detecting gas leaks. Discuss the ethics of using dogs (instead of humans) for tasks that might injure or kill them.

Sweet Smell of Success
Ask your students which domestic animal they believe has the strongest sense of smell; the list may include dogs, cats, hamsters, guinea pigs, turtles, mice, fish, birds, and other common pets. Then have your students work in groups to design an experiment to conduct on the pets they have at home—an experiment that could prove or disprove their hypotheses. (Make sure that each group contains at least one student with a pet at home.) For example, one experiment might involve presenting a subject—an animal or a human being—with a set of three cups, only one of which is hiding a morsel of food. The goal would be to determine whether the subject is able to choose the cup with food beneath it using only its sense of smell. The experiment should be repeated several times for the sake of consistency, and students could vary it using different types of food. Once students have completed their experiments and recorded their data, they can compare their results and attempt to determine whether their initial hypotheses were correct.

What Else Can Dogs Do?
Throughout history, dogs have been trained to perform a wide variety of tasks—guiding blind people, herding sheep, hunting, rescuing lost mountain climbers, acting in movies, sniffing out bombs and drugs, guarding houses, and even fighting crime, among others. Ask your students to research various ways in which dogs have been used to perform tasks—either at the present time or at any other time in human history—with an emphasis on understanding what goes into their training. In addition to using the Internet and other standard research sources, the students might want to consider calling a local dog-training school. When their research is complete, ask each student to create a list of five new activities that dogs might be trained to perform, as well as a regimen for training a dog to perform each one.

The Hidden Life of Dogs
Elizabeth Marshall Thomas. Pocket Books, 1996.
This astonishing work asks and answers a question about dogs that's so simple that apparently no one has ever tackled it before: "What do dogs want?" The author, a trained scientist and novelist, brings her storytelling skills to bear in this beautifully written exploration.

Dog's Best Friend: Annals of the Dog-Human Relationship
Mark Derr. Henry Holt, 1997.
This book presents a combination of stories and research about the relationship between dogs and humans over many time periods and cultures.

Definition: An often-hereditary illness resulting partially from a mutated gene in an individual.Context: Many genetic diseases are passed down from one generation to the next but are not evident until the organism reaches adulthood.

This lesson plan may be used to address the academic standards listed below. These standards are drawn from Content Knowledge: A Compendium of Standards and Benchmarks for K-12 Education: 2nd Edition and have been provided courtesy of theMid-continent Research for Education and Learningin Aurora, Colorado.

Grade level: 6-8, 9-12Subject area: life scienceStandard:
Understands the genetic basis for the transfer of biological characteristics from one generation to another.Benchmarks: Benchmark 6-8:
Knows that the characteristics of an organism can be described in terms of a combination of traits; some traits are inherited and others are the result of interactions with the environment.

Benchmark 9-12:
Knows ways in which genes (segments of DNA molecules) may be altered and combined to create genetic variation within a species (e.g., recombination of genetic materials; mutations; errors in copying genetic material during cell division).

Benchmark 9-12:
Knows that mutations and new genetic combinations may have positive, negative, or no effects on the organisms.

Grade level: 6-8, 9-12Subject area: life scienceStandard:
Knows about the diversity and unity that characterize life.Benchmarks: Benchmark 6-8:
Knows evidence that supports the idea that there is unity among organisms despite the fact that some species look very different (e.g., similarity of internal structures in different organisms, similarity of chemical processes in different organisms, evidence of common ancestry).

Benchmark 9-12:
Knows how organisms are classified into a hierarchy of groups and subgroups based on similarities that reflect evolutionary relationships (e.g., shared derived characteristics inherited from a common ancestor; degree of kinship estimated from the similarity of DNA sequences).